Ink



Patented Feb. 18, 1936 mo s ENT E INK Lawrence McLaughlin,

Riverside, Ill., assignor to No Drawing. Application October 10, 1929,

Serial No. 398,721

1 Claim.

This invention relates to an ink and method of making the same, and more particularly to an ink adapted to be applied to vitreous enamel surfaces and to a method of applying the ink to such surfaces.

An object of the invention is to provide an improved ink and method of making the same applicable to surfaces of articles.

In accordance with one embodiment of the invention, the ink is composed of boiled linseed oil as a vehicle, a metal or a metallic oxide as a pigment, and a flux such as borax. The solid ingredients are finely ground and thoroughly mixed with the vehicle, and the ink is applied by moistening a type plate with the ink, transferring the impression from the plate to a pad of rubber or similar yielding material, and then impressing the pad upon the surface to be inked. Where a plurality of colors are to be applied, a plurality of impressions in inks of the desired colors are successively applied to the pad, and are then simultaneously applied to the surface.

The invention will be more fully understood from the following description.

In preparing the ink, a fiux such as borax is mixed with a metallic pigment such as cobalt oxide in the proportion of about three parts of pigment to one part of fiux. Lead oxide may also be added to impart a luster to the finished surface. These ingredients, finely ground, are thoroughly mixed together in a paint mill or similar apparatus, and are incorporated in a linseed oil varnish. Suflicient linseed oil is used to give the ink the consistency of printers ink. The

' linseed oil varnish is previously boiled or bodied to give it the proper degree of viscosity. The cobalt oxide and borax are suspended in the boiled linseed oil vehicle. The viscosity of the vehicle must be closely controlled, but will vary somewhat with the nature of the surface to which the ink is to be applied, the manner of applying it, and other factors. The viscosity of the ink should be about the same as that of printers ink, and may readily be determined by test.

In practicing the invention the ink may be applied to a vitreous enamel surface by the offset printing process in which the ink is applied to a metallic type plate from an. inking roller and a resilient pad is used to transfer the impression from the type plate to a vitreous enamel surface as for instance the surface of a calling dial for a telephone apparatus. Such a vitreous enamel surface. may be formed in accordance with the disclosure of L. I. Shaw Patent No. 1,806,183, issued May 19, 1931.

After the vitreous enamel surface has been impressed in the manner above described, it is placed in a furnace where it is heated to a high temperature to drive off the vehicle and cause the pigment and flux to fuse and unite with the enamel surface of the plate.

While the invention has been described with particular reference to the number plate of a calling dial, it will be understood that it is applicable to the inking of ceramic surfaces of various shapes and kinds. The composition of the ink may be Widely varied in accordance with the colors desired, the nature of the surface to which it is to be applied, and other factors. Thus, other vitreous enamel fiuxes than borax may be used, such as glass or lead borate, and any of the following substances, as well as mixtures thereof, are suitable as pigments: Manganese oxide, nickel, iron, cop-per, chromium, selenium red, as well as other pigments known in the art.

The ink is also Well adapted for use in decalcomania processes, since it may be applied directly to paper without objectionable running or spreading, whence it may be'transferred to the surface to be inked.

Various other modifications of the invention will occur to those skilled in the art, and the following claim is intended to include such modifications as fall within the spirit of the invention.

What is claimed is:

An ink adapted for use on vitreous surfaces, consisting of approximately three parts of finely divided cobalt oxide, one part of borax, and sufficient boiled linseed oil to form a suspension of the cobalt oxide and borax in the boiled linseed oil vehicle.

LAWRENCE MoLAUGI-ILIN. 

